JP-A-2002-170915 (referred to as a prior art, hereinafter) discloses the above kind of conventional heat sink. The conventional heat sink comprises a heat transfer vessel provided inside with a channel and a heat transfer accelerator (such as a fin or a turbulent flow accelerator) in the channel. In the heat transfer vessel, formed are an entrance side space for a cooling fluid and an exit side space for the cooling fluid. Making the cooling fluid flow from the entrance side space to the exit side space causes a base plate to be cooled, and thereby, electronic components mounted to the base plate to be cooled. The entrance side space for the cooling fluid and the exit side space for the cooling fluid are provided separately on the ends of the both sides of the heat transfer vessel as shown in FIG. 3 of the prior art or formed on the same end on one side of the heat transfer vessel so as to be separated from each other as shown in FIG. 2 of the prior art.
Patent Reference 1: JP-A2002-170915